BC MoTT Enhanced Bridge Deck Inspections
Multi-year bridge deck condition survey and inspection program covering 20 bridges across British Columbia, using drone-based defect-mapping and other investigative measures to guide province-wide asset renewal planning.
Client: BC Ministry of Transportation and Transit (MoTT)
Location: Multiple locations across all regions of British Columbia
Project Type: Bridges
About This Project
Bridges are among the most critical and most quietly ageing pieces of British Columbia’s transportation network. Understanding their current condition is the first step to keeping them safe and planning renewal work before small issues progress to become costly ones.
ISL served as prime consultant to the BC Ministry of Transportation and Transit (MoTT) on a multi-year condition survey program covering 20 bridges across the province, spanning the southern Fraser Valley, the Sea to Sky corridor, the Southern Interior and central BC’s Highway 16 corridor and beyond. The bridges varied widely in scale, ranging from 12 m to 380 m, and included a mix of girder bridges, steel truss structures, highway overpasses and underpasses.
As prime consultant, ISL organized and coordinated every aspect of the program: field inspections, traffic control, materials testing and final reporting. Field work was carried out in partnership with Metro Testing, with ISL leading inspections, component reviews and drone surveys while Metro Testing handled materials testing and sampling. ISL was the Ministry’s single point of contact throughout, managing scope, schedule and quality across a wide network of sites spanning the province.
Each bridge received a thorough condition assessment, including a variety of inspection methods, including visual observations of the deck and surrounding structure, delamination surveys, concrete cover testing, half-cell potential (CSE) testing and chloride sampling to check for corrosion risk. This data was prepared for inclusion into service life models and cost analyses for the structures, giving MoTT the capability to determine clear, evidence-based picture of where to prioritize future maintenance and rehabilitation dollars.
One of the biggest challenges was reaching every part of a bridge safely and thoroughly. Areas like deck joints, overhangs, pier supports and railing connections are difficult or impossible to inspect on foot, particularly on the program’s longer structures. ISL’s team used aerial drones equipped with high-resolution cameras to capture these hard-to-reach areas, then layered that imagery directly onto CAD drawings as well as point cloud three-dimensional models. MoTT and future maintenance contractors could now see exactly where repairs were needed, mapped precisely onto the bridge drawings instead of scattered across inspection photos.
The program’s scope grew over time to include additional testing methods, which brought new scheduling pressures on the longest bridges, where limited daylight, weather and crew availability all had to be balanced and night shifts required on some structures to avoid disruption to heavy traffic volumes. ISL adapted by bringing in additional staff through its partnership with Metro Testing, keeping every bridge on schedule within its assigned inspection season.
The success of the program speaks for itself: MoTT has re-engaged ISL for a second consecutive multi-year term, a strong vote of confidence in ISL’s ability to deliver consistent, high-quality bridge condition data across some of the province’s most geographically dispersed infrastructure.
Challenges & Solutions
- Challenge: Hard-to-reach inspection points — deck joints, overhangs, pier supports and railing connections — were difficult or impossible to assess safely on foot, especially on the program’s longer bridges.
Solution: ISL deployed aerial drones with high-resolution cameras to inspect these areas, then layered the imagery onto CAD drawings to create precise, spatially mapped defect data for MoTT and future maintenance contractors.
- Challenge: Adding new testing methods partway through the program created scheduling pressure on the longest bridges, where limited daylight, weather and crew availability all had to line up.
Solution: ISL brought in additional staff through its partnership with Metro Testing, keeping every bridge on track within its assigned inspection season and used night shifts when necessary.
- Challenge: Coordinating field inspections, traffic control, Ministry staff, and materials testing across sites spread the length of the province, from Hope to Terrace to Fort St. James to Valemount, required careful logistics.
Solution: ISL managed all scheduling, staffing and sub-consultant coordination as prime consultant, acting as the ministry’s single point of contact throughout.
Key Results
- Delivered condition survey reports for 20 bridges province-wide, ranging from 12 m single-span structures to a 380 m steel truss bridge
- Performed visual condition surveys, half-cell potential (CSE) testing, resistivity (Wenner probe) surveys and chain-drag delamination surveys across all structures
- Conducted deck coring, concrete cover determinations and chloride depth profile testing to assess corrosion risk and remaining service life
- Introduced aerial drone inspection with high-resolution imagery superimposed on CAD drawings, enabling spatially referenced, quantitative defect mapping in place of standard inspection photography
- Produced service life models and life cycle cost analyses (LCCA) for each bridge, supporting data-driven prioritization of rehabilitation and renewal investments
- Coordinated field inspections, traffic control and materials testing sub-consultants across geographically dispersed sites from Hope to Terrace to Fort St. James to Valemount
- Maintained CSE testing schedules on the program’s longest bridges (up to 380 m) despite constraints from daylight, weather and crew availability
- Re-engaged by MoTT for a second consecutive As and When program term, reflecting sustained confidence in ISL’s inspection and reporting quality